Question

A 4.80-kg ball, moving to the right at a velocity of +3.36 m/s on a frictionless table, collides head-on with a stationary 6.10-kg ball. Find the final velocities of (a) the 4.80-kg ball and of (b) the 6.10-kg ball if the collision is elastic. (c) Find the magnitude and direction of the final velocity of the two balls if the collision is completely inelastic. (a) Number Units

Answer 1

here,

m1 = 4.8 kg , m2 = 6.1 kg

initial speed of 1 , u1 = 3.36 m/s

a)

let the final speeds of balls be v1 and v2

using conservation of momentum

m1 * u1 = m1 * v1 + m2 * v2

4.8 * 3.36 = 4.8 * v1 + 6.1 * v2 ...(1)

and

using conservation of kinetic energy

0.5 * m1 * u1^2 = 0.5 * m1 * v1^2 + 0.5 * m2 * v2^2

4.8 * 3.36^2 = 4.8 * v1^2 + 6.1 * v2^2 ...(2)

from (1) and (2)

v1 = - 0.4 m/s

v2 = 2.96 m/s

b)

the final speed of 6.1 kg ball is 2.96 m/s

c)

let their final speed be v

using conservation of momentum

m1 * u1 = (m1 + m2) * v

4.8 * 3.36 = ( 4.8 + 6.1) * v

v= 1.48 m/s